The present invention relates to new fluorinated cationic acrylic copolymers, to aqueous compositions comprising said copolymers, and to their use for coating and impregnation of various substrates such as textiles, leathers, wood, nonwovens, metals, concrete and, more particularly, for coating and impregnation of building materials to provide durable protection against water and soiling. It also relates to the solid substrates, notably the building materials so treated.
It has been known for a long time that fluorinated compounds, and in particular compositions based on fluorinated polymers, provide protection of various supports such as paper, leather or textiles against water, oil and grease.
It is also known that fluorinated polymers can effectively protect building materials against external attacks such as water and soiling.
Compositions disclosed in international patent application WO 97/39072 are thus useful for this latter application. These are, however, aqueous compositions of fluorinated cationic acrylic copolymers which still contain non-negligible quantities of organic solvent.
Patent application WO 00/05183 describes a composition which is also useful for protecting building materials against water and soiling, which comprises a copolymer such as those disclosed in WO 97/39072 cited above, as well as a penetrating assistant which is a surface active compound which facilitates penetration and wetting of a limestone and/or silicate substrate. On a practical scale, the presence of this assistant also requires the presence of an organic solvent which may be toxic and is thus little appreciated by the users.
Patent application WO 97/00230 describes a composition based on a fluorinated polymers comprising a silane monomer, useful for treating porous substrates such as building materials to protect against water and grease spots. This composition is aqueous and stable, and presents good abrasion resistance.